The purpose of this study is to determine whether a breast-conserving treatment program of limited surgery and definitive radiation offers equivalent local control and survival to mastectomy in-patients with early stage breast cancer. Patients were randomly assigned to either primary surgery or primary irradiation. Patients treated with mastectomy were offered breast reconstruction. All patients underwent complete axillary node removal; those patients with pathological positive lymph nodes and those with negative lymph nodes who were estrogen receptor negative received chemotherapy. This protocol has been closed to new accrual since 1989, but it remains open for follow up. Long term follow up for this landmark study is essential to our understanding of this disease process. A 15 year follow up meta analysis is in preparation for publication.